4.1 Properties of Minerals

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Vocabulary

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Inorganic: An object is not made of living thing or the remains of the living objects.
Crystal: A solid which atoms are arranged in a pattern that repeats all over again.
Element: A substance that is made of a single atom.
Compound: A substance that is made of two or more atoms that are chemically joined.
Mohs hardness scale: a scale that measures the hardness of a rock
Streak: A powder color of a mineral
Luster:How minerals reflects light on their surface
Cleavage: An ability for minerals to split
Fracture: The way how minerals appeal when they split

Outline

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What Is a Mineral?

• A mineral is a solid with different chemicals
  • There are more than 3,000 minerals in the world
    • Since there are more than 3,000 minerals, there are more probably 3,000 chemicals you need to mixed to make rocks

Naturally Occurring

• there are many requirements for a rock to be classified as a mineral
  • things such as cement, brick, steel, and glass are not classified as a mineral because of the fact that they are man made objects and didn't particularly form naturally

Inorganic

• in order for a rock to be classified as a mineral it has to be in organic
  • this means that the mineral can't be formed from an object that was once living

Solid

• a mineral always has to be solid to keep its shape by squeezing molecules tightly together so none of them could be spread out

Crystal Structure

• the particles of a mineral lines up in a pattern that repeats again and again
  • sometimes the the crystal structure is obvious to predict that it is a mineral.
    • the only thing that could see a crystal structure is under a microscope

Definite Chemical Composition

• minerals has certain types of elements in definite proportions
  • Almost all minerals are compounds in which they are made of more than two elements
    • The elements that make up a compound are said to be chemically joined together

Identifying Minerals

• in California's gold rush in the year of 1849 people were trying to find gold
  • That time they didn't get to find any gold, but instead they were finding minerals that looked exactly like gold
    • The people that time didn't now what to do with the minerals and it was hard for them to identify what they were by only their colors

Hardness

• You can see if the rock is hard by the Mohs hardness scale
  • Mohs hardness scale invented in 1812 created by Friedrich Mohs
    • To try to test the hardness you have to scratch each rock with each other

Color

• A color of a mineral is easy to observe
  • But color can be used to identify a few minerals
    • Some minerals can have many colors and some may have only one

Streak

• Streak is the mineral's powder
  • You can observe the streak by rubbing mineral against a piece of unglazed tile
    • The color of the mineral might vary, but the streak does not

Luster

• Luster is how the mineral shines in the reflection
  • This is another way to identify minerals
    • Minerals are usually shiny because of metal contained inside

Density

• Density is the mass in a given space or mass per volume
  • Density is a little bit like how much more heavier a mineral is then another
    • People find out the Density by a weighter

Crystal System

• crystals of minerals grow atom by atom in order to form the mineral's particular crystal structure

Cleavage and Fracture

• when a mineral breaks apart that could really help in identifying the mineral
  • cleavage is when a mineral splits easily along flat surface areas
    • Depending where the mineral is arranged depends if the mineral has cleavage
      • when a mineral breaks apart in an irregular way it's called fracture

Speical Properties

• minerals can also be identified by their physical properties
  • fluorescence is when minerals glow under ultra violet light that has a property